Eccentric pump with screw rotor and stator - has cavities between stator and housing

摘要

The eccentric screw pump has a driven screw rotor of circular cross-section. This rotor rotates within a helical stator made from flexible material held in a circular rigid casing. The rotor carries out additionally an opposite circulating movement around the axis of the stator. The space for the rotor within the stator has two parallel sides whose ends are joined by semicircular arcs. The stator has two internal, diametrically opposite cavities. These cavities are arranged about the axis of symmetry which is also the axis of symmetry of the elongated stator slot parallel sides. High pumping pressures can be achieved with this pump and it has good sealing characteristics.